ArticleOriginal scientific text

Title

On the isoperimetry of graphs with many ends

Authors 1

Affiliations

  1. Laboratoire de Mathématiques E. Picard, UMR CNRS 5580, Université Paul Sabatier, 118, route de Narbonne, F-31062 Toulouse Cedex, France

Abstract

Let X be a connected graph with uniformly bounded degree. We show that if there is a radius r such that, by removing from X any ball of radius r, we get at least three unbounded connected components, then X satisfies a strong isoperimetric inequality. In particular, the non-reduced l2-cohomology of X coincides with the reduced l2-cohomology of X and is of uncountable dimension. (Those facts are well known when X is the Cayley graph of a finitely generated group with infinitely many ends.)

Bibliography

  1. [ABCKT] J. Amorós, M. Burger, K. Corlette, D. Kotschick and D. Toledo, Fundamental Groups of Compact Kähler Manifolds, Math. Surveys and Monographs 44, Amer. Math. Soc., 1996.
  2. [Av] A. Avez, Variétés Riemanniennes sans points focaux, C. R. Acad. Sci. Paris Sér. A-B 270 (1970), 188-191.
  3. [CGH] T. Ceccherini-Silberstein, R. Grigorchuk and P. de la Harpe, Amenability and paradoxes for pseudogroups and for discrete metric spaces, preprint, Université de Genève, 1997.
  4. [Du] M. Dunwoody, Cutting up graphs, Combinatorica 2 (1982), 15-23.
  5. [Ge] P. Gerl, Random walks on graphs with a strong isoperimetric property, J. Theoret. Probab. 1 (1988), 171-188.
  6. [Gr89] M. Gromov, Sur le groupe fondamental d'une variété kählerienne, C. R. Acad. Sci. Paris Sér. I 308 (1989), 67-70.
  7. [Gr] M. Gromov, Asymptotic invariants of infinite groups, in: G. A. Niblo and M. A. Roller (eds.), Geometric Group Theory, Vol. 2, London Math. Soc. Lecture Note Ser. 182, Cambridge Univ. Press, 1993.
  8. [GLP] M. Gromov, J. Lafontaine et P. Pansu, Structures métriques pour les variétés riemanniennes, Textes Mathématiques, Cedic, Fernand Nathan, 1981.
  9. [Ka] M. Kanai, Rough isometries and combinatorial approximations of geometries of non-compact Riemannian manifolds, J. Math. Soc. Japan 37 (1985), 391-413.
  10. [Kri] V. Krishnamurty, Combinatorics, Theory and Applications, EWP PVT, New Delhi, 1985.
  11. [Pi] C. Pittet, Fοlner sequences in polycyclic groups, Rev. Mat. Iberoamericana 11 (1995), 675-685.
  12. [St] J. Stallings, Group Theory and Three-Dimensional Manifolds, Yale Math. Monographs 4, Yale Univ. Press, 1971.
  13. [SW] P. Soardi and W. Woess, Amenability, unimodularity, and the spectral radius of random walks on infinite graphs, Math. Z. 205 (1990), 471-486.
Pages:
307-318
Main language of publication
English
Received
1997-11-28
Accepted
1998-04-27
Published
1998
Exact and natural sciences